1. Field of the Disclosure
The invention relates to a cooking apparatus with a cooktop composed of a glass or glass-ceramic material, wherein at least one heating element and at least one lighting element are disposed in the region below the underside of the cooktop, wherein the heating element is applied to the underside of the cooktop by means of a spring-action pressing device, directly or indirectly, for example, by pre-stressing one or more spring elements or spring-action fixtures or mounting plates.
2. Description of Related Art
Cooking apparatuses having lighting elements in which the lighting elements are used for the display of operating states are known from the prior art. Induction cooking apparatuses are usually designed today with a glass-ceramic panel as the cooktop. Basically, other materials such as pre-stressed soda-lime glass or borosilicate glass, for example, can also be employed as cooktop material, if a thermal overheating of these materials that are more sensitive to temperature can be avoided. All materials, glass ceramics as well as soda-lime glass or borosilicate glass, are brittle-fracture materials. In order to avoid glass breaks during assembly, transport, or in the operation of the cooking apparatus in the kitchen, structural measures must be considered so that a break in the cooktop is avoided. A glass cooktop or a glass-ceramic cooktop cannot equilibrate the energy of a falling pot by means of deformation of the surface, as a metal surface could, for example. Rather, the energy must be dissipated into the environment by oscillations. If this dissipation is prevented, then the impact load leads to a break of the cooktop. For this reason, cooktops are incorporated in such a way that they can evade impact loads, for example, when a pot falls onto the cooktop. The heating elements, in particular, induction coils, are pressed by spring action to the underside of the cooktop; thus these elements can also yield in the case of an impact load.
Lighting elements serve for marking cooking zones or for visualizing operating states, such as cooking conditions or hazardous circumstances. In order to assure easy identification, the lighting elements should be brought as closely as possible to the underside of the cooktop. Then losses due to scattering are kept small and a good image sharpness and brightness of the lighting elements can be achieved. The lighting elements themselves can be glass or glass ceramics, and therefore have the property that the light output along the length of the lighting element can be defined as needed. In the case of an impact load (falling pot) onto the cooktop, there is now a double risk in this case. On the one hand, the cooktop can strike the lighting element and break during the deflection. On the other hand, however, the lighting element can also be damaged, or both components can be rendered unusable simultaneously by the impact.
A cooking apparatus in which a heating element is disposed underneath the cooktop is known from DE 38 31 233 A1. In this case, the heating element is supported by a housing. A housing extension is screwed onto the housing laterally. The housing extension supports a lighting means, which couples its light into a lighting element formed as a light guide. The light guide is thus formed ring-shaped and surrounds the heating element.
Another cooking apparatus is known from DE 40 02 322 A1. Just like in the case of DE 38 31 233 A1, an annular light guide is used here as a lighting means. This light guide is embedded in the insulating material of the heating element.
Another ring-shaped or annular light guide is known from DE 43 35 893 A1.